A data sequence can store any data in sequential order. That is, data is read one item at a time, like an assembly line. A stack is another way of describing a data sequence. A stack keeps track of data in a first in, last out order (also known as “FILO”). Alternatively, this can be described as last in, first out (“LIFO”). Figure 5.6 illustrates a common example of a stack, in which plates coming from the dishwasher are added to the stack and immediately removed for service. The first plate added to the stack might never even be used if plates continue to be added as fast as they are removed.